Intermitter



June 6, 1944. c. MQ'OLEARY V 2,350,472

' INTERMITTER 'Filed Feb. 7, 1942 ,2 Sheets-Sheet 1 charms/ZI-ozewmysmog' BY 7 I ATTORNEY Patented June 6, 1944 UNITED STATES PATENTOFFIGE Application February 7, 1942, Serial No. 429,937

8 Claims.

The present invention relates generally to intermitters, or in otherwords fluid pressure actuated devices for intermittently causing upflowof liquid in a well, and has to do, more particularly, with what arecommonly known in the oil well industry as bottom hole intermitters,wherein oil is permitted to rise to a head above the intermitter valveduring the filling period or cycle, until it has reached a predeterminedweight value, whereupon a change of the valve cuts ofi the entry offurther oil, and admits casing pressure for the purpose of blowing tothe surface, in the second or production cycle, the previouslyaccumulated head of oil.

In all such intermitters it is common practise to pack off the casingpressure for the prevention of back pressure on the producing zone,since any such back pressure would have a tendency to prevent rise ofwell liquid under existing formation pressure during the filling cycle.This is particularly important in wells of low formation pressure, inmany of which the formation pressure is normally such that the fillingcycle is slow and slugs of oil can be blown out only at widely spacedintervals.

With the above in mind it is one of the objects of the present inventionto provide an intermitter having a valve structure along somewhat thesame line as that included in my former application, entitled "Timedintermitter, and filed January 21, 1941, under Serial Number 375,158,patented September 7, 1943, No. 2,328,841, improved, however, in certainrespects which render the present device more positive in action, andmore certainly proof against back pressureon the producing formationunder all circumstances.

According to another phase of the present invention, it is an object toprovide an intermitter in which the arrangement is not only such as toavoid danger of back pressure against the producing formation, but inwhich means are included for the purpose of substantially assistingformation pressure during filling cycles, for shortening such cycles aswell as promoting increased oil production, the arrangement preferablybeing such that material assistance is afforded the oil during thefilling periods, to the extent of reducing to a minimum the backpressure held on the producing formation.

A still further object of the present invention is the provision ofanintermitter valve which will steadily maintain positive, efiectiveaction, and will be proof against fluttering in its use in formations ofsufiicient pressure to build up what are :known as "false filling heads,or in other words build up pressure belowthe intermitter valve, during aproduction cycle, sufiicient to cause an uprush 'of oil during theinitial portion of the-succeeding filling cycle.

With the foregoing general statements and objects, further features,objects and advantages of th invention may be better understood and morethoroughly appreciated, in the course of the following description indetail, and by reference to the accompanying drawings, illustrating thesame, and forming a part of this specification. In these drawings;

Figure 1 is a vertical, sectional view through a portion of a wellcasing and liner, illustrating the manner of installing the intermitter.

Figure '2 is a detail vertical, sectional view through the int'ermitter,showing the parts in position during a filling cycle.

Figure 3 is a similar View, showing the parts in position during ablowing or production cycle, and also illustrating the use of means forassisting the filling operation in wells of low formation pressure, and,

Figures 4, 5 and Gar detail, transverse sectional views, takenrespectively on lines l4,

5-5 and 66 of Figure 2.

Referring now to the above figures of the drawings, there is shown inFigure 1, a vertically elongated casing l-U, carried on the lower end ofwell tubing H by virtue of a coupling at l2, and depending within theWell casing l3. This casing 19 serves as a filling chamber above theintermitter valve arrangement which is housed therein, in connectionwith-a valve body 14 having wall apertures [5, to permit fluidunderpressure in the casing l3to enter the valve body [4. Below theapertures l5, packing I6, around the casing l0, and between the same andthe well'casing [3, serves to prevent the passage of fluid pressuredownwardly to the producing formation.

The lower end of casing 19 is connected, by a coupling H, to the upperend of macaroni tubing l8 which extends downwardly to a desired pointwithin the liner l9, pendent from the well casing L3, to thus providefor upflow of oil into the lower end of the intermitter casing it.

As seen in Figures 2 and 3, the bottom coupling i! preferably supports afoot valve 26 at the upper end of "the macaroni tubing I8, and in thepresent construction, the cage 2-l of this foot valve serves as asupport for a self-centering valve pin 22, which rises axially of thelower,

portion of casing l9. The lower end of this valve pinZZ has a convexl ycurved head 23, held in movable relation on a fiat supporting surface,

by means of a flanged sleeve 24, spaced from, and

axial opening through which the hollow or tubular valve stem 26 of theintermitter valve depends. Thus the bottom portion 25 of the valve bodymay have packing 21 therein, around the stem 26, to prevent downwardflow of fluid pressure, and may also serve as an abutment for the upperend of a valve controlling coil spring 28. This spring is disposedaround that portion of stem 26, below the valve body, in-a compressedcondition to exert a predetermined downward pressure at its lower endagainst a valve seat collar 29.

The collar, 29, it will be noted, is threaded on the lower end of stem26, and. presents a downwardly facing valve seat 30'around the lower endof the stem channel, for effective engagement with the upperrounded endof the valve pin 22, when the intermitter valve is in its lowerposition, to cut off the upfiow of well liquid through the stem and islocated below the closed bottom 25 of the valve body and isolatedthereby from the interior of the valve'bocly.

The upper portion of valve body l4 forms there- In its closed position,at the start of a filling,

cycle, the intermitter valve as a whol is held in its upper position,with fluid pressure valve'33 in seated position by reason of the actionof fluid pressure from the casing 13, through openings I 5 and the flowreducing channels, this action of the fluid pressure being the lowerlarger surface of said valve. In this position of the parts, shown inFigure 2, the liquid or well fluid valve is open by reason of thespacing of th valve seat 30 vertically away from the valve pin 22. Thusthe way is free for rise of oil under formation pressure, through thestanding valve 20, and through the axial flow channel 35 of theintermitter valve and its stem 26, to form a slug above the valve duringthe filling cycle.

Opening of the fluid pressure valve 33 of this invention, normally heldtightly seated by direct action of easing pressure as above, isaccomplished by the combined pressures exerted by the controlling sprin28 and the liquid load within casing l0 and tubing l I on the uppereffective area of the valve which is exposed to such load. In this wayit isonly necessary to vary the effective tension of the spring 28 inorder to adapt the valve in any instance to the available casingpressure.

Whenthe rise of liquid in'the tubing above the valve 33 produces such apressure that, combined with thetensionof spring 28, casin pressure isovercome and the valve thus forced downwardly to unseated position, thismovement is quick, positive and steady, and the arrangement is such thatwhen the valve has been opened, it will remain steadily open withoutdanger of fluttering or false movements at any time, due to thefollowing:

The eifective area of valve 33 is its seating area, and this area, itwill be noted, is made slightly larger than the effective area of thepiston 3|, so that when the valve is seated, casing pressure actingagainst the lower effective area of the valve tends to hold it tightlyon its seat against the fluid head building up in the tubing on thevalve and tending to unseat the latter.

When, however, the weight ofthe tubing load increases to the pointwhere, in opposition to casing pressure acting as above, it is capable,with the assistance of spring 28, of overcoming such opposition, itforces the valve downwardly to unseated position.

Immediately upon unseatin of the valve 33, casing pressure is thenactive upon only the smaller effective area of piston 3|, so that duringthe fiow period in which the accumulated slug of oil is being raised,there is substantially less closing force against the valv than therepreviously existed when the valve was seated, and hence there islesstendency for the valve to seat until there is a pressure drop in thetubing.

Due to the foregoing it is plain that mor pressure is necessary in thetubing to bring about downward or unseating'movement of the valve 33,than is thereafter necessary to hold the valve in unseatedpositionduring the flow period. Hence it follows that before the valvecan be returned to its seat the pressure in the tubing must dropconsiderably below that pressure which was re quired therein to unseatthe valve.

During unseating of the valve 33 under tubing load, the effective areasof both the valve and the piston 3| are high pressure areas, andcontinue so while the load is lifted in the tubing and until there is apressure drop therein. When there is apressure drop in the tubing,incident to discharge of the slug, the area around the valve head 33 andthe upper end of the piston 3| is converted into a low pressure area, towhich casing pressure can communicate only through the flow reducingchannels 32, so that such casing pressure will thus act against the highpressure lower end of the piston to quickly and positively shift thevalve member upwardly so that the valve will be seated.

During the above described operation, and immediately upon movement ofthe pressure control valve 33 to unseated or lower position, liq uidvalve seat 30 engages valve pin 22 and thus cuts off further rise ofwell liquid through the intermitter valve channel. It will be noted thatthe effective area of the stem 26 is not greater, and is preferablyless, than the effective area'of valve pin 22, so that when the liquidvalve is closed, the valve collar 29 is either balanced in the pressureof the-well liquid or subjected to downward pressure thereby, thusaiding the spring 28 and the fluid pressure around valve 33 to defeatany tendency toward pumping move'- ment of the intermitter valve whichmight other-j wise occur in the changing pressures of the well liquid.

The arrangement of the present invention is thus effective for thepurposes stated, with very little differential as regards the Weight ofthe liquid of'the slug over and above the casing positive in its action,effectively guided in its movements, and free of danger ofhammering inunseat the gas control valve and in this way causing a fluttering orunstable'action of valve.

' Not infrequently wells are encountered which build up considerablepressure below the intermitter valve during the blow of a slug in theproduction cycle, so that when the blow-down the is reached and the gascontrol valve'seats and the liquid valve opens, there is a very suddenuprus'h of well liquid in what .is known as a false filling head. Withthe present valve structure such a situation is well taken care ofbecause the force of the uprush of liquid can only operate to hold thegas control valve tightl against its seat. In the various features thusfar described, the construction shown in Figure 3 is precisely that ofFigure 2, but. recognizing the advantage of the use of such anintermitter in many wells which produce oil in substantial quantity,though under low formation pressure, there is shown in Figure 3 anadditional arrangement whereby to facilitate the rise of well liquidinto the filling chamber in a manner which reduces the back pressure onthe producing formation by aerating and lightening the incoming wellliquid, and insures rapid filling of the chamber during each fillingcycle.

To the above end it is proposed that to the valve head 33 be added apipe or stem 36 rising to the upper portion of the filling chamberwithin casing Hi. The lower end of this pipe or stem 36 may be threadedin connection with the valve head at 3'! so that its bore forms acontinuation of the intermitter valve channel 35. A guide may be used onthis stem, since it rises and falls with the intermitter valve, and suchguide may, take the form of radiating arms 38 extending from a collar 39around the stem, with anti-friction rollers 49 at the ends of such armsto engage the inner surface of the casing 10.

With such an arrangement, a minute pressure inlet port 4| is formedthrough the depending stem 26 of the intermitter valve below the piston3|, and thus in communication with the channel 35, the port beinginclined to direct the fluid pressure upwardly at all times forinjection into the rising liquid, whereby to aerate and lighten theliquid and thus assist the liquid in its flow upwardly into the fillingchamber. This will tend to reduce back pressure on the producingformation and ofiset any lack of formation pressure which may have to bemet with.

To prevent blowing the oil upwardly into the production line, a mushroomdeflecting head or cowl 42 may be used on the upper end of the risingstem or pipe 36, with downwardly directed discharge openings 43 insuringdelivery of oil downwardly into the filling chamber, and permittingseparation of gas therefrom as well as unobstructed rise of such gasinto the production line.

The use of such an arrangement will be considerable practical advantagein many instances, andneed not vary the described operation-of theintermitter in any respect other than possible modification of thetension of spring 28 tocompensate for the added weight imposed on theintermitter valve by the rising stem 36 and its parts. I

'Having thus fully'disclosed the invention what is claimed is:

1. In a well flowing device of the bottom hole intermitter type havingan eduction passage, a valv housing forming a gas flow passage openinginto said eduction passage and having a closed bottom, a unitary valvevmember having pressure responsive means for shifting said member in onedirection in operation by pressure in the gas passage, and having aliquid-flow passage therethrough openinginto the eduction-passage, valvemeans opening and closingsaid gas passage, said member also having aportion .depending movably through said housing bottom, and valve meanscooperating with the said zdepending portion of the valve member,respectively closing and opening the liquid flow passage as the gas flowpassage is opened and closed, the last mentioned Valve means being belowthe bottom of the housing and thereby isolated from the gas passage. 2.In a well flowing device of the bottom hole intermitter type having aneduction passage, means forming a gas flow passage opening into saideduction passage, a unitary'valve member having pressure responsivemeans in said gas flow passage for shifting the member in one directionin operation by pressure in the gas passage, said valve member having aliquid flow passage therethrough opening into the eduction passage, andhaving valve means at its upper portion opening and closing said gaspassage, and valve means cooperating with the lower portion of saidmember, and isolated from the gas passage, respectively closing andopening the liquid passage as the gas passage is opened and closed.

3. In a well flowing device of the bottom hole intermitter type havingan eduction pipe, means forming a gas fiow passage opening into theeduction pipe, a unitary axially shiftable valve member, having pressureresponsive means for shifting the same in one direction in operation bypressure in said gas passage, and having an axial liquid flow passageand valve means around the upper end of said liquid passage closing andopening the gas passage as the member is shifted upwardly anddownwardly, valve means cooperating with said member at the lower end ofsaid liquid passage respectively, positively opening and'closing saidliquid passage as the gas passage is closed and opened, and meansisolating the said liquid valve means from the gas passage.

4. In a well flowing device of the bottom hole intermitter type, havingan eduction passage, a valve housing forming therein a gas fiow passageopening into said eduction passage, a valve member shiftable axially insaid gas passage including gas pressure responsive means for shiftingthe same in one direction, and having upper valve means opening andclosing the gas passage, said valve member having a depending stem andan axial liquid flow passage opening at its upper end into the eductionpassage, valve means cooperating with the lower end of said stemeffective to open and close said liquid passage as the gas valve meansrespectively closes and opens the gas passage,- and said housing havinga closed bottom surrounding the'stem of said valve member and isolatingthe liquid valve means from said gas passage.

'5. In a well flowing device'of the bottom hole intermitter type, havingan eduction passage, means forming a filling chamber in communica: tionwith said eduction passage, means forming a gas flow passage incommunication with the filling chamber, a unitary valve memberinfluenced in its movements by pressure in the gas passage, and havingupper valve means opening and closing the gas passage, said valve memberhaving an axialliquid flow passage, lower valve means cooperatingtherewith forclosin and opening said liquid passage, and a'hollow.stem'rising from said valve member, area continuation of said liquidpassage :within, and opening into, the filling chamber. I

6. The device as set forth in claim 5, with flow deflecting means at theupper outlet end'of said stem. I

7. In a well flowing device of the bottom hole intermitter type, havingan eduction passage, means forming a filling chamber in communicationwith said eduction passage, means forming a gas flow passageinecommunication with said filling chamber, a unitary valve member,influenced in operation by pressure in said, gas passage, and havingupper valve means'opening and closing the gas passage, said valve memberhaving an axial liquid flow passage, lower valve mean'aisolated fromsaid gas passage and cooperating with .said valve member for closing andopening said liquid passage, said valve memher having a gas jetting portin communication at all times withthe gas passage and opening into theliquid passage in the direction of flow of liquid therein.

8. In a well flowing device of the bottom hole intermitter type, meansforming an eduction passage, a valve housing open at its top into saideduction passage andhaving a closed bottom and a=gas pressure inletopening therein above said bottom; a vertically shiftable unitary valvemember exposed at its top to-the eduction passage and including aportion forming therearound a gas'flow passage in said housing, valvemeans movable with said portion of the valve member under gas pressurein said gas passage to close off the said passage with respect to theeduction passage when the valve member is in its upper position, saidvalve member also including a lower portion depending movably throughsaid housing bottom, and also having an axial liquid flow passagetherethrough, and valve means cooperating with said: lower portion ofthe valve mem berand positively opening and closing the lower end of theliquid flow passage When the valve member is respectively in its upperand lower positions, said last named valve means being located below thebottom of the housing and isolated thereby from the gas flow passage.

. CHARLES M. OLEARY.

